Basil Crow

Would this not be better reported/patched against OpenJDK's `java.net.URLClassLoader`? While we could work around the issue as in this PR, I'm not sure we want to maintain custom class loading...

> This isn’t an issue with URLClassLoader itself — it’s designed to work correctly in typical Java applications, where an extra 10MB per class loader is a reasonable overhead in...

Thanks, this is excellent! Can you please write a description of the changes to help with reviewing?

Can we keep as many of the calls to `registerAsParallelCapable` as possible while still achieving the goal of this PR, which is to decrease memory usage?

Thanks. I appreciate the description of the implementation-level changes to each file. I think what I'm still missing is a high-level description of the overall change, and how that solves...

@dukhlov I have been travelling this week and have not had enough time to work on this PR. I want to get this shipped, but this PR is still a...

I am working on some performance improvements for job loading, but this is next on my TODO list after that. Hopefully by next week.

(I plan to squash-merge this with @jtnord listed as a co-author as well, because he came up with the important idea of the string interning lock.)

I ran the Tomcat tests from https://github.com/jenkinsci/packaging/tree/master/molecule/servlet with the WAR from this PR, and the test passed, so I think this PR is ready for merge.

Very impressive change. Thanks again @dukhlov! I saw that you had removed the cleanup to `UberClassLoader` as part of simplifying this PR for review. We'd still be interested in that...